The applicant used his own resources in developing this invention and there was no assistance from the United States Government.
1. Field of the Invention
Electrical cables, especially communication cables, comprise a number of individual conducting members. These conducting members may be wires such as copper wire or may be a fiberoptic. The members are individual conductors of information.
Unfortunately, the communication cable may be damaged or cut or broken or even severed. With damage to the cable, it is necessary to splice together the individual conductors of information.
The communication cable as manufactured has a protective outer sheath of material. With damage to the communication cable, this outer protective sheath is broken and it is possible for extraneous material such as water, snow, dust and dirt to work into the interior of the communication cable and maybe even into the individual conductors of information.
In practice, and after the communication cable has been repaired, a splice case is positioned around the splice area of the cable so as to act as a protective outer sheet of material in the spliced area.
The splice case must be weather proof to rain, snow, hail, freezing weather, combination of rain and freezing weather, heat and high temperatures, ultra-violet light from the sun, from swaying due to the wind blowing the communication cable, fuel resistant to materials such as gasoline, diesel, oil and kerosene, flame resistant to low temperature flame, and must be resistant to the internal air pressure inside of the cable as the internal pressure inside of the cable is about 10 pounds per square inch, PSI.
Further, the splice case must be of such a construction that it can be readily assembled in the field. Quite often, in repairing the communication cable, it is necessary to be elevated off of the ground maybe 15 feet or more such as 30 feet. Therefore, the repair person must be able to manipulate the splice case for ease of positioning over the spliced area of the communication cable. Many times the cable is underground or in a vault.
2. Description of the Prior Art
The splice case of U.S. Pat. No. 3,337,681 is still used. Further, the splice case of U.S. Pat. No. 3,337,681 minus the flexible, yieldable material 24, i.e., neoprene, polyethylene, polypropylene or lead as specifically provided in claim 11 of U.S. Pat. No. 3,337,681 is extensively used in the United States. It is estimated that there are approximately 200,000 splice cases sold each year in the United States and these splice cases do not have the flexible yieldable material 24 of the splice case U.S. Pat. No. 3,337,681.
Instead of the flexible yieldable material 24, there is used a mastic. One of the mastics used is a B Sealing Tape developed by Bell Laboratories. This mastic is placed between the flanges 16 of two half tubular members 14. The mastic seals between the two flanges and provides good protection from the elements for the conducting cables 50 and 52 inside of the tubular member 10. There is a disadvantage with the use of this mastic. The disadvantage is that if it be necessary to open the tubular member 10, it is difficult because of the adhesive property or the stickiness of the mastic. Once the tubular member 10 is open and the repair work accomplished, it is then difficult to join together the two half tubular members 14. Before joining the two members 14, the mastic must be removed from the flanges 16. The removal of the mastic from the flanges 16 is time consuming and difficult which adds to the expense of repairing the conductors 50 and 52. Often, all of the mastic cannot readily be removed from the flanges.
The B Sealing Tape, on a weight basis, comprises approximately 27% butyl rubber, approximately 41% carbon black, and approximately 27% polybutene with minor quantities of other additives.
A second mastic, referred to as R Sealing Tape, was introduced about 1980. This mastic is releasable so as to make the entry of the tubular member 10 easier. A problem exists in regard to the quality control of the R Sealing Tape in that it is difficult to accurately make the desirable adhesive property. If the R Sealing Tape is made sufficiently sticky or sufficiently adhesive to stay in place during installation of the conducting cables 50 and 52 in the tubular member 10, it is difficult, when another repair is made, to open the tubular member 10. Further, in opening the tubular member 10 the shape of the tubular member 10 is often damaged or destroyed requiring full replacement of the member. On the other hand, if the R Sealing Tape does not have sufficient adhesive property and is not sufficiently sticky, the R Sealing Tape falls away during installation on the flanges 16, and there results an imperfect seal of the tubular member 10.
The uncured R Sealing Tape comprises acrylic rubber, hydrated, aluminum, chlorinated polyethylene, polymeric plasticizers, and polyisobutylene.
It is desirable to have a mastic which has good adhesive properties and good sealing and resilient properties and yet allows the two half tubular members 14 to be readily separated from each other even though joined by the mastic. To the best of my knowledge and information, the prior art has not solved this problem.
The objective of this invention is to provide a mastic or a composite sealant which attaches itself to the closure of the flanges 16 during installation so that the sealant will not fall away from the closure or splice case thereby making it easier to assemble the splice case;
A further object is to provide such a mastic which acts as a sealant between the two half members of the splice case and yet which mastic allows the splice case to be readily opened to make adjustments in regard to the electrical conductors inside of the splice case.
In other words, the mastic or sealant must have sufficient adhesive properties to adhere to the closure when the two half-members of the closure are being joined and being used and yet these adhesive properties must readily yield to the separation of the two half-members of the closure if it be desirable to re-enter the splice case;
The sealant must positively seal the closure members of the splice case and yet must make it possible to readily open and separate the two closure members of the splice case;
An object of this invention is to provide a composite sealant comprising a sealing material and also an adhesive material so that the adhesive material will adhere to part of the splice case while changing its configuration to function as a sealing material while the sealing material will change its shape to provide a sealing member with respect to the other part of the splice case and yet allow the two half-members of the splice case to be readily separated;
The deformable member should be compounded so that it wants to return to its original shape and size when the two half-members are separated;
Another object of this invention is to provide a composite sealant comprising a deformable member for sealing with part of the splice case and also an adhesive member for attaching itself to the other part of the splice case and which composite sealant is resistant to rain, snow, heat, fuel, sunlight, ultra-violet light, flame-resistant, and of sufficient body to resist movement due to an internal pressure of about 10 pounds per square inch inside of the cable inside of the splice case;
Another important object is to provide an inexpensive composite sealant having a deformable member for adjusting to the configuration of the splice case and also an adhesive member for adhering to part of the splice case;
An additional object is to provide such a composite sealant which can be readily inventoried and stored for use;
A further object is to provide such a sealant which is adaptable to many shapes and sizes such as in cross-sections, round, square, and rectangular;
A further object is to provide such a composite sealant which can be stored in straight sections or coiled round on itself such as in a tape;
A further object is to eliminate the yieldable liner in the half tubular members and to replace the liner with a less expensive composite strip comprising a sealant and an adhesive.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by the practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.